There are known machines as staplers e/o riveting compressed air machines provided with valves and control and regulation means allowing the single hit or automatic repetition operation or the release of a single fixing mean, for instance a metallic staple, a pin, a nail, etc., or the release of a plurality of such fixing means in sequence, with different timing.
The actuating of the two different modalities is generally obtained by partially or completely, up the stop, pressing the trigger of the utensil or pressing two separate triggers or pushers.
Such trigger or pusher, in fact, subsequently crushes two separate command pivots placed side by side, that act on respective pneumatic valves.
Typically, partially pressing the trigger, is obtained the single hit operating, and the automating working pressing it to the stop of the stroke.
A disadvantage of such type of operation consists in the excessive sensibility and attention required to the operator for pressing the trigger, in order to avoid to unintentionally and unawares operate the automatic operation rather than the single hit.
They are also known staplers machines in which the trigger commands only the automatic operation of the machine that can be inhibited to have the single hit through the operation of a pusher or button, that it operates an opportune pneumatic circuit.
In this case, the disadvantage resides in the discomfort of employment of the machine, because the operator is forced, to get the single hit, to press the trigger with the index and contemporarily the button with the thumb of the same hand, by realizing a non optimal handling and, therefore, inadequate firm and sure of the utensil.
In the known stapler machines, the fixing means are hammered in the piece to be worked through a beating blade, that is powered by an compressed air piston.
The piston is brought then in the initial position through the opening e/o closing of opportune valves or other pneumatic organs, typically distributors or exchangers automatically or manually commuted.
A drawback of such known machines consists in their structural and constructive complexity, that comprises numerous parts and components, resulting therefore expensive to build and to assemble.